Need help, throwing codes!!!

[rotwiler]

About 2 months ago my car sat for awhile, so I jumped it and when it started I threw P0135, P0200, P1153. After about 2 minutes the car felt normal and no more issues. I wrote down the codes and reset the pcm due to emissions check was coming due in a few days.
Today, I was on my way to work, taking off from a stoplight 1/2 throttle and car sounded funny..power was less and seen the check engine light blinking on dash. I was getting ready to pull over and engine sounded normal again and all was good. So I checked the codes and this is what it set off. All these were set off at the same time.
P1416 Air system bank 2
P1153 Ho2S Bank 2 sen 1 insuff switching
P0300 Random multiple cyl misfire detected
P0200 Injector Circuit cylinder Malfunction
P0135 02S Heater circuit bank 1 sensor 1 malfunction

I checked plug wires(they are MSD and have about 3,000 miles on them), LT headers have been on car a few years and never once threw a code. Didn't see any leaks around injectors, oil level on car is perfect and never has burned any oil. When I added the LT's I also made the check valve restrictor plate, to keep from burning up the check valves. Just trying to figure out how to pinpoint whats going on, since so many threw at the same exact time. My 02's on the back are deleated, but still have sims on there, just because I was lazy to remove them. My guess is starting to lead to a bad 02, but then 2 banks showed a code which seems odd..heater on one and insuff switch on other.. This is driving me crazy.. I was just about ready to go for a plate n20 kit or do a cam and some other mods, now I am having to let car sit. The only issue at all I know the car has is a very very small header leak on both sides closest to the front of car. I know this only because I can see a light haze of carbon around the top of the flanges..but no ticking is heard..I am going to put locking bolts on there soon..
All I have is a Predator tuner, so I don't have a real scanner. After I cleared the codes I made a few WOT runs and had zero issues, but I know something is getting ready to go and don't want to get stuck out in the middle of nowhere. When this happended the other night, at first I thought something broke since car basically went into major limp mode, sounded like a electric car,,really muffled sound, no roar at all, like car was on 2 cylinders.

[0rion]

po200 is the code I would focus on. 1416 is a check valve, 1153 and 135 are fairly common with headers even though you haven't had them until now, and 200 is causing 300. Go to gearchatter.com and read the diagnostic aid for the 200 code. Probably just a cruded up connection somewhere or a mouse made a home out of some wiring while it was being stored. That should at least get you started.

[rotwiler]

Now I am only throwing the P0200 and P0300 so your right. Injector Circuit is what I need to focus on.. But now I have no idea where to start. I looked at all the injectors, plug wires etc all looks good. Then I noticed on the pcm the wire harness that comes out under the firewall a green wire and had some nicks or maybe chew marks from a mouse maybe. But didn't look like it was all the way through to cause a bad connection. Car still runs fine for a day or so, then will act up on random basis. Not sure what or where the other wires are I need to track down...Found a PCM diagram so will look it over.. I am pretty sure it is mouse damage or corrosion since it started happening the first time I drove the car after it sat for 3+ weeks. I did notice some white powdery residue on the aluminum engine parts and the little chew marks on the wire..so will take out the pcm, clean connectors, check all the wires over and fix any bad ones, cover them all with tubing and ties. Hopefully it will fix it.